[clang] [C2y] Support WG14 N3457, the __COUNTER__ macro (PR #162662)

[via cfe-commits]

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@@ -226,7 +226,7 @@ class Preprocessor {
       LangOptions::FPEvalMethodKind::FEM_UnsetOnCommandLine;
 
   // Next __COUNTER__ value, starts at 0.
-  unsigned CounterValue = 0;
+  unsigned long CounterValue = 0;
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Sirraide wrote:

I’d prefer it if this was a `uint32_t` rather than an `unsigned long` but I don’t feel too strongly about it.

https://github.com/llvm/llvm-project/pull/162662